Rock drill



Jan'. 29, 1929. 1,700,378

A. H. SKAER El' AL RocK DRILL Filed July 11. 19.22 zsheets slner 1 1,700,378 A. H. SKAER ET AL ROCK DRILL Filed July 11. 1.922 2 Stiens-Sheet 2 Jan. 29, 1929.

attorney- Yatented Jan. 29, 192.9.

llllllll@ STATES SENCE.

ARTHUR H. SKAER, THEODORE E. BAKKER, AUGUST IC. 'KTTERJOI-IN, AND OMAR E.

CLARK, OF DENVER, CLGRADO, ASS G'lEl-S, BY I'ZElliiE lllSGIl'lVIl-JNTS, TO GARD- NEB-DENVER COMPANY, 0F QUNCY, ILLE?? 01S, COREATN 0F. DELAWARE.

ROCK DRILL.

Application iletl July 11,

.he present invention relates more particularly to rock drills ot the type having a eter tor operating on the drill steel and ithcr inotor for eli'ecting the rotation oi the t ln certain types or construction where the steel sticks in the hole and the steel rotating inotor continues in operation a rela- Yively great ainount of strain is produced upon the transmission gear between the niotor and the chuck which is apt to result in stripping the gears.

@ne ot the primary objects oi the present invention is to provide a structure by which this difficulty is entirely overcome.

@ne embodiment ot the invention is illustrated in the accompanying drawings, wherein Figure l .is a vievv in elevation of the iront portion oi a well lrnown type et ha inner drill with the head plate of the chuck rotating inotor ren'ioved,

Figure 2 is a cross sectional view therethrough,

Figure 8 is a plan view with the inotor shown in section,

Figure el a longitudinal sectional'view,

Figure 5 is an edge view oi' the spring washer employed,

Figure 6 is a face view of the saine,

Figures 7, 8 and 9 are detail sectional views, respectively, illustrating dillerent types oi slip connections.

ln the embodiment disclosed in Figures 1 lo (l, the. drill includes a suitable cylinder ini-unber- 10 containing a hainnicr piston 1l having an extension 12. A hood 13, carried by the front end ot the cylinder ineniber l0,

houses a rotatable tool holder in the torni of a chuck sleeve lil. This sleeve is provided with a soclret 15 adapted to receive the rear end oi a drill steel 16 that is loosely fitted in the chuck sleeve and suitably inter-locked thereJ with so as to ro tate with said sleeve in a inanner well understood. The hammer' extension 12 of the piston 11 in the present ernbodinient is adapted to strike the rear end of the. drill steel 16, as illustrated in Figure e.

A drill rotating motor is located on the cylinder member 10, and as shown, consists of a housing 17 containing intermeshing gear pistons 18. Motive fluid is supplied to the housing 17 on one side ot the piston through a passageway 19, and a suitable exhaust 20 1922. Serial No. 574,193.

allows the escape from the opposite sides. Connected to one of the gear pistons 18 is a. shaft 21 provided with a worin 22 that in iuesh with a. worin whoe1 23 rotatably n'iounted on the rear end oi the chuck sleeve 1.4:. Said chuck sleeve is reduced in dialneter 'to receive said worin wheel, thereby providing an abutment shoulder 24C ilor one side oi said worin wheel A iriction washer Q5 inay be interposed between the abutment shoulder and the worin wheel. T he rear terminal portion of the sleeve lll is threaded to receive a nut 26 forming an abutment on the opposite side of the worin wheel 23 of the abutment shoulder 24, and interposed between said nut Q6 and the wheel are friction washers 2.7 and a spring washer 28, the latter being preferably termed in oppositely disposed curves, shown in Figures 5 and 6.

ylhe friction washers Q5 and 27 and the spring washer 28 provide a friction clutch o-r slip connection between the worin wheel Q3 and the chuck sleeve 14C. This connection is relatively tight or tast, so that under ordinary conditions the rotation of the gear pistons 18 will transmit inotion to the shaft 21, and thence through the worin 22 to the worin wheel 23, and this worin wheel will be, in etiect, lined to the chuck 14, so as to insure its rotation and consequently the rotation oi the drill steel. ln tactwhen the drilling piston 11,--12 is inactive, the clutch. or slip connection is such that the motor will stall it the drill steel becomes stuck beiioi'e the slip connection will give materially.

In operation, however, as long as the haininer piston l1-1l is in operation rapidly repeated blows delivered a list the drill steel will cause a vibration of the machine which appearsto lessen the tractive or friction connection between the Worin wheel 23 and chuck sleeve 14, sothat while the drill steel will be rotated under norinal conditions, if it becomes stuck and the hannner piston continues to operate, the drill rotating` niotor will continue to move and the slip connection will perniit the worin wheel to rotate with respect to the chuck sleeve 14. This has proven a very material advantage, for if the worin wheel 23 is last to the chuck sleeve 14, it has been found that the operation of the drill rotating pistons 18, coupled with the vibration of the drill due to the piston 11-12, causes a continued rotation of the Worm, even though the worm wheel isstopped. As a, consequence l; in rockdrilling apparatus, theco-mbination with a rotatable drill chuck, Ona/drilling motor iorV operating on a steel in the chuck, and `.means forlrotating the chuck, includingfa worm, gear surroundingU a, portion, 0f. the chuck, ay driving. worinfengaged with= the worm gear, and a'slip connection between the the thread of the worm acts as a wedge and in. time bears with such great pressure agrain-.1:t theteeth ofthe wormurlicelthat either` the wormor the-wormy teeth are aptto be stripped. Experience has demonstrated that this is entirely overcome by the present construction. While, therefore, it is peculiarly eiiec tive in connection with the worm gearing, it is also of utility with other` types.

As suggested modifications of the above described structure, attention is invited to Figures 7, 8 andi). ln Figure 7 the chucksleeve element is designatedA lst, and rotatably mounted thereon is the worm wheel 23 op eratedby the wormdesignated 22, A 't'ric tion washer 25a-is interposed between one side. of the worm gear 23a and the abutment shoulderta, whileanother friction washer Qahhas abearing against,v aA washer 2 8A held by anutQf.I Y InFigureS the .chuck-elementY Ml? has ashoulder 24D androtatablyv mounted onrsaidielement 14h is the :worm wheel 23h engagedzby thefworm 22D.v The inner-side oi' the.y worin` wheel1 is tapered, and bearing against4 the `beveled faces areY friction washers. Q51? and 27h, theiormer bearing' againstthe abutment -shoulden Qaband the latter beingheld :in place .byahnt5261?.,v lnFigure 9 the chuck` element 14C has a shoulder 24?, and is rotatably surrou-ndcd'by-a worin wheel 23, the inner face oitwhich is beveled, A), friction,washer,c is interposed between one side of-the worm wheel 28 and the `sl-roulder- 24?. Bearing against Ythe -innerbeveled face of. the worniwheelQBQ-.is another friction washer 27C A.within ,which-isf-lecated a cone or` wedge element QSCIthat-is borne against by a holding nut 26C. The worm which engages the-worm wheel Q3@ is shown at 22C. Obviously these three modifications performithe same functions as the embodiment lfirst described. e

From the foregoing, it is thought that the construction, operation and many advantages oi? the herein described invention `willbe apparent to those skilled in the art, without further description, and it will be understood that various changes 4inthe size, shape, proportion and minor details of construction may be resorted to without Adepartingfrom the spirit 'vor scope o'l the invention.

Having thus fully ldescribed our invention, what we claim as new and desire to secure by Letters Patent, is

worin gear and chuck.

2. In rock drilling apparatus, the combina tion Lwith ,a ,rotatable drill chuck, of a drilling motor for operating on a steel in the chuck, and rmeans for7 rotating thechuck, including amotor independent of the'drilling motor, a worm rotated by` the motor, aworm gear`Y driven by the worm and mounted to rotate on the chuck when the chuck is heldlagainst rotation, anabutmentV on the chuck .tor one side of the worm gear,v another al'nitments on the. other side ofL the worm gear, anda slip connection between the `latter abutment. and

the worm gear.

the stoppage .of the drill steel.

4. ln rock drilling apparatus, thefcombination with aA rotatable chuck lilavingmeans therein for. loosely interlocking with a drill steel placed therein, of a drillingmotor in cluding a hammer piston that delivers rapidly repeated hammer blowsupon a steel placed in the chuck, a gear-mounted to rotate on the exterior of the chuck when the Achuck isheld against rotation, a chuckrotating naotor gearedto said gear, and ai'rietionslip coupling between the gear and the chuck upon which it is mounted for normally causing the chuck to be rotated by the gear.

ln testimony whereof,l we affix-'our signatures.V

anfriiun H. simian. r-nnononnn Banken. AUGUST H; KATTERJOHN; OMAR-bn. CLARK, 

